I don’t think he necessarily is.
Temptation, say in the case of adultery, is not the same as lust but lust is acting on the temptation even if in the mind only. The lust, which is the same as adultery, comes after the temptation and is something done by the one lusting.
Likewise a person to entertains murder in their heart has done more than just be angry with their brother, they have had that proverbial “Yeah, I’d do it if I could get away with it.” sort of moment too.
Well said ...